Related Experiment Video
Updated: Jul 1, 2026
11:20
Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
Detection of polarization in the cosmic microwave background using DASI. Degree Angular Scale Interferometer
J M Kovac1, E M Leitch, C Pryke
1Department of Physics, Center for Astrophysical Research in Antarctica, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637, USA. john@hyde.uchicago.edu
Nature
|December 20, 2002
Summary
Scientists detected polarization in the cosmic microwave background (CMB) radiation. This finding strongly supports the standard cosmological model and its conclusions about the Universe's origin and evolution.
Area of Science:
- Cosmology
- Astrophysics
- Cosmic Microwave Background Radiation
Background:
- The standard cosmological model explains cosmic microwave background (CMB) temperature fluctuations as acoustic oscillations from primordial density fluctuations.
- Recent CMB measurements have yielded significant insights into the Universe's origin, evolution, and composition.
- The theoretical framework predicts CMB polarization levels based on temperature fluctuations with no free parameters.
Purpose of the Study:
- To critically test the standard cosmological model by measuring CMB polarization.
- To validate cosmological parameters derived from CMB measurements.
Main Methods:
- Utilized the Degree Angular Scale Interferometer (DASI) to detect CMB polarization.
- Analyzed temperature fluctuations and their predicted polarization patterns.
Main Results:
- Successfully detected polarization of the CMB with high confidence.
- Observed polarization levels and spatial distribution align excellently with standard theory predictions.
Conclusions:
- The detection of CMB polarization provides strong evidence for the validity of the standard cosmological model.
- The results confirm the theoretical predictions for CMB polarization, reinforcing our understanding of the early Universe.
Related Concept Videos
01:25Atomic Absorption Spectroscopy: Interference
Interference leads to systematic error in atomic absorption (AA) measurements by enhancing or diminishing the analytical signal or the background. These interferences can be grouped into three main categories: spectral interference, chemical interference, and physical interference.
Spectral interference occurs when signals from other elements or molecules overlap with the analyte signal, falsely elevating or masking the analyte's absorbance. This interference can be corrected using Zeeman,...
Spectral interference occurs when signals from other elements or molecules overlap with the analyte signal, falsely elevating or masking the analyte's absorbance. This interference can be corrected using Zeeman,...
01:30Atomic Emission Spectroscopy: Interference
In atomic emission spectroscopy (AES), high-temperature atomizers excite a broad range of elements and molecules that generate complex emissions from sources such as oxides, hydroxides, and flame combustion products in the flame or plasma. Several strategies can be employed to minimize spectral interferences caused by overlapping emission lines or bands. These include increasing instrument resolution, choosing alternative emission lines, optimally placing the detector in low-background regions,...
01:30Electronic Distance Measuring Instruments
Electronic Distance Measuring Instruments (EDMs) are essential tools in modern surveying, offering precise distance measurements by emitting electromagnetic signals and calculating the time required for these signals to travel to a target and return. Two primary types of signals are used in EDMs — light waves and microwaves — each suited to specific environmental and distance requirements. Light-wave-based EDMs utilize either infrared or laser light, providing high accuracy over short distances...